Apparatus for cutting weft in automatic looms



Nov. 4, 1941. R; G, TURNER 1 2,261,635

APPARATUS FOR CUTTING WEFT IN AUTOMATIC LOOMS Filed Sept. '7, 1940 INVENTOR RICHARD G.TURNER I H115 D ATTORNEY Patented Nov. 4, 1941 APPARATUS FOR CUTTING WEFT IN AUTO- MATIC LOOMS Richard G. Turner, Worcester, Mass, assignor to Crompton & Knowles Loom Works, Worcester, Mass, a corporation of Massachusetts Application September 7, 1940, Serial No. 355,856

Claims.

This invention relates to a method and apparatus for cutting a weft thread in automatic weft replenishing looms and it is the general object of the invention to lead the thread over the bobbin rings of the depleted bobbin and cut it by the rings of the fresh bobbin as the latter is inserted into the shuttle.

In my co-pending application Serial No. 344,308 I have shown a shuttle the eye of which is so constructed as to deliver the weft at the top of the shuttle. That application is directed more particularly to the shuttle while the present application relates to the cutting of the thread which is placed in cutting position partly by the top delivering shuttle eye.

Bobbin changing looms ordinarily operate with shuttles having holding jaws which grip metallic rings on the head of the bobbin. The magazine of such a loom carries a supply of reserve bobbins each of which is also provided with metallic rings. At the time of transfer the incoming or fresh bobbin is forced downwardly against the bobbin in the shuttle and there is a temporary contact between the rings of the incoming and the outgoing bobbins. It is the general purpose of my present invention to utilize this temporary contact between the rings to sever the thread.

The invention further relates to a thread guide on the shuttle which cooperates with the shuttle eye to cause the thread to lie across the top of the shuttle and between the two sets of rings. A further object of the invention is to provide a thread placer, which may be in the form of a brush, against which the thread is moved by the advancing lay, the brush being placed preferably between the guide andthe cloth to draw the thread taut between .the guide and shuttle eye and between the two sets of bobbin rings.

The axis around which the transferrer arm moves in the usual multi-color weft replenishing loom'is above the top of the shuttle under the magazine, with the result that the incoming bobbin, which follows generally the path of the transferrer arm, will move downwardly in a direction having a forward component while in contact with the depleted bobbin in the shuttle. The proportions of the transferrer arm are such that in order to move the incoming bobbin through a distance equal to the diameter of the rings necessary to effect ejection of the depleted bobbin, the lay must move forwardly a distance equal approximately to the radius of the forward component of the down motion of the incoming bobbin and there is therefore an appreciable rolling contact between the rings of the two bobbins involved in the transfer. The rolling is in a direction across and rearwardly with the shuttle and has a range of appreciable extent during the forward stroke of the lay. If the thread is held at any point within this range of rolling contact it will be severed by the pressure exerted between the two sets of rings. If both sets of rings should be held against free rolling they will scrape or slide along each other throughout the aforesaid range. object of my present invention to make use of this rolling or sliding contact between the two sets of rings to cut the weft thread.

As faras the transferring operation is now understood the two bobbins are in contact with each other throughout the greater part if not all of the time during which the fresh bobbin is moving into the shuttle. When the exhausted bobbin starts to move down it spreads the shuttle jaws until its horizontal diameter has reached the bottom of the jaws. Shortly thereafter the jaws will try to move toward each other in an effort to force the outgoing bobbin downwardly by a wedging action, but by this time the rings of the incoming bobbin have reached the tops of the jaws and prevent the latter from having a wedging action on the outgoing bobbin. This I believe is one condition which contributes to the duration of the rolling contact already mentioned and permits an appreciable cutting range to exist transversely of the shuttle through the greater part of the time during which the full bobbin is moving into the shuttle.

With these and other objects in view which will appear as the description proceeds, my invention resides in the combination and arrangement of parts hereinafter described and set forth.

In the accompanying drawing, wherein a convenient embodiment of 1 my invention is set forth,

Fig. 1 is a front elevation of certain parts of a weft replenishing loom having my invention applied thereto, parts being in section and shown in normal non-transferring position,

Fig. 2 is a view similar to Fig. 1 but showing the parts in transferring position with the rings of the incoming and outgoing bobbins in contact\with each other at the beginning of they the rings. This radius is ordinarily greater than cutting operation,

It is another.

Fig. 3 is a horizontal section on line 33 of Fig. 2,

Fig. 4 is a vertical section on line 4-4 of Fig. 1,

Fig. 5 is a detailed diagrammatic view of a portion of Fig. 4 showing the manner in which the thread placer locates the thread with respect to the thread guide,

Fig. 6 is a diagrammatic plan showing the relation of my invention to other loom parts and the cloth being woven, and

Figs. 7 and 8 are diagrammatic views showing the relation of the incoming and outgoing bobbins during a transferring operation.

Referring particularly to Figs. 1 and 2, I have shown a lay L having a shuttle race l and'provided with a slot H for the outgoing or depleted bobbin. The lay moves back and forth in the loom in the usual manner and reaches so-called front center position for each pick or beat of the loom. A reserve bobbin magazine M of any approved form, such for instance as that in my copending application Serial No. 328,482, holds a reserve bobbin B in transfer position directly over the shuttle S when the lay is on front center on weft replenishing beats of the loom. bobbin has a. head I2 with the usual spaced metallic rings I3 and has also a tip l4 around which the weft W unwinds during weaving. As shown herein the magazine has inner and outer plates and I6, respectively, which guide the heads and tips of the reserve bobbins to the transfer position indicated by bobbin B, Fig. 1. Yielding supports I! for the head and tip of the bobbin B hold the latter in transfer position. The magazine is pivoted as at I 8 to a fixed support K.

The shuttle has the usual pair of spring jaws [9 which hold the metallic rings of the depleted bobbin D and these jaws are held in place partly by a transverse screw 2| and partly by a sheet metal holder 22 having an inclined bobbin guiding surface 23 and an upper horizontal plate 24 extending along the top of the shuttle to afford means for anchoring the holder 22 to the shuttle by means of a screw 25.

The other end of the shuttle is provided with an eye E having a vertical longitudinally extending thread slot across the upper part of which projects. innerand outer thread hooks 3| and 32, respectively. The inner hook 31 projects forwardly while the outer hook 32 projects rearwardly under an overhanging guard 33. The eye includes a block of metal 34 held to the shuttle as at 35. Located in the inner part of the slot 30 are yielding friction pads 36 between which the weft runs and by which it is tensioned.

In order to adapt the shuttle eye E for use with my invention I provide it with means for effecting top delivery of the thread. The shuttle eye is accordingly made with an upwardly and forwardly preferably curved guide chamber 31 which terminates in a thread groove 38 extending inwardly toward the longitudinal center of the shuttle. When the thread leaves the thread passage 30 it is directed upwardly along the guide 31 and is delivered at the top of the shuttle eye. When the shuttle is moving to the right as viewed in Fig. l the thread will extend along the guide notch 38, but when the shuttle is moving to the left the thread reeves over a guide pin 39. The foregoing description of the shuttle is thought to be sufiicient for present purposes, the significant feature being that the thread is delivered from the top of the shuttle eye at a point between the front and back walls of the shuttle so that it can extend over the top of the shuttle toward The reserve a the left as suggested in Fig. 1 when the shuttle is in transferring position. Reference may be had to my co-pending application Serial No. 344,308 for a more extended description of the shuttle eye. I do not wish necessarily to be limited to the particular type of shuttle eye shown either herein or as more fully described in my last named co-pending application since the present invention requires only that some form of shuttle eye be used which will deliver the thread in such a way that it can extend across the top of the shuttle. It is desirable to have the weft under some tension as it passes through the shuttle eye, as will be pointed out hereinafter, and the pads 36 or some equivalent means may be employed for this purpose.

As shown diagrammatically in Fig. 6 the lay has a-box back 40 and reed 4| which define the shuttle path. The lay is shown in front center position so that the reed is against the fell F of the cloth C, and the thread T attached to the selvage 42 extends diagonally forwardly and toward the adjacent end of the lay and over the top of the shuttle to the shuttle eye. A pneumatic thread extractor 45 has a forwardly extending wing 45 lying over a mass of deformable material 47 such as plush mounted on the lay. The thread willbe moved down on the deformable material by the wing when the extractor tube 45 descends to a position behind the thread T on transferring beats of the loom. For further reference to the construction and operation of the thread extractor reference may be had to prior Patents Nos. 2,199,296 and 2,207,089.

The weft replenishing mechanism includes a transferrer arm 55 movable about a supporting stud 56 which as shown in Fig. 4 is usually spaced at a level substantially above the top of the shuttle. This relationship is not an essential feature but it has an advantage which will appear. The transferrer arm is caused to descend on weft replenishing beats of the loom by well-known mechanism not shown, and the heel 5'! of the transferrer arm moves in a path concentric with the axis of the arm along the dot and dash curved 1ine shown in Fig. 4.

During the transferring operation the reserve bobbin B is forced downwardly by the transferrer arm against the depleted bobbin in the shuttle, thus causing contact between the sets of rings on the two' bobbins B and D. When the rings first contact each other the two bobbins are in the relative position shown in Fig. 7 with the top and reserve bobbin slightly in front of the bobbin in the shuttle. In order to complete transfer, the transferrer arm must move down a distance equal substantially to the diameter of the rings, but during this movement the lay will move forwardly a distance equal approximately to the radius of the bobbin rings because of the proportions of the transferrer arm as customarily made. At the endof the transfer operation, therefore, the parts will be in some such position as that suggested in Fig. 8.

As shown in Fig. '7 the centers of the two'bobbins B and D lie along a line a which is diagonal and inclined forwardly. When the transferring operation is complete the line joining the centers of the rings of the two bobbins is substantially vertical, as indicated by line b in Fig. 8. The contact between the two sets of rings therefore moves rearwardly during the act of transfer in a direction transverse of the longitudinal axis of the shuttle. This movement may be accompanied either by rolling engagement between the sets of rings, or by a sliding motion, depending upon whether the bobbins are free to turn or are held against rotation. The depleted or outgoing bobbin moves downwardly through the shuttle slot 1 l on the lay and exerts a tension on its weft thread T tending to pull it out of the shuttle eye.

In order to locate the thread T for cutting I provid a placer mechanism which acts to position the thread so that it will be between the two sets of rings. Referring to Fig. 5 it will be noted that the top of the shuttle adjacent the ring N of the bobbin is provided with a slot l9 into which the plate 24 is set. The top H of the shuttle projects above the top of plate 24 and provides a space in which I locate a hook 12 near the rear part of slot 10. This hook may be of metal and is secured in any approved manner to the plate 24 and has a forwardly opening mouth 13 to receive the thread. Secured to the fixed support K is a holder I5 which may be made of wire and held at its upper end by a screw 16. The lower end of the wire has a shell 11 secured thereto from which depends a brush 80 having flexible bristles. The brush is adjustable in a direction transversely of the path of the shuttle by reason of the screw 16 and will ordinarily be so placed as to be slightly behind the hook 12 at the time of cutting. It will also be seen from Fig. 6 that the brush is located between the hook l2 and the cloth being woven so that any bend in the weft caused by the brush will not occur between the shuttle eye and the hook 12.

When the lay is moving forwardly on a beat of the loom in which transfer is to occur, the thread will extend from the shuttle eye over the top of the shuttle and into the warp shed H. A transferring operation having been called, the thread extractor will b moved downwardly with the transferrer arm and wing 46 will depress that part of the thread extending from the shed to the top of the shuttle, thereby bending the thread T downwardly and creating a slight tension in it. As the lay continues to advance the reserve bobbin will move out of the magazine and will have its initial contact with the depleted bobbin in the shuttle. By this time the shuttle will have been moved far enough forward by the advancing lay to caus the stationary brush to sweep the thread into the hook I2. During the course of the actual transferring operation the thread T will be held taut between the delivery eye of the shuttle and the hook l2 and lie between the rings of the two bobbins. The shuttle pads 36 and brush 8'.) are primarily responsible for the tautness of the thread, but the wing 46 is also a contributing factor. The hook 12 and the shuttle eye are so placed that a straight line drawn between them such as that taken by the thread T will lie between the rings of bobbins B and D and within the zone or range of contact between the two sets of rings. The rings act to sever the thread when they engage each other as already described. The thread being thus cut will present two free ends the left of which as viewed in Fig. 1 will be sucked into the pneumatic thread extractor 45 or controlled in some other manner, and the right end of which will move out of the shuttle eye by reason of the downward pull of the outgoing bobbin.

In addition to the rolling of the rings already mentioned there is another condition which assists the thread cutting operation, namely, the fact that the thread extends diagonally across the rings 26. As seen in Fig. 3 the thread is oblique with respect to the rings which cut it, and since there are usually thre rings on each bobbin spaced in the direction of the shuttle length, there is a slight range transversely of the shuttle within which the thread contacts the rings. Thus, if the outermost pair of rings on bobbins B and D nearest the bobbin tip should contact immediately behind thethread, the latter will be cut by one or the other of the remaining pairs of rings due to the rearward direction of the thread as it extends toward theguide hook 12.

. From the foregoing it will be seen that I have provided a simple means by which the thread T may be cut at the time of transfer. It will further be seen that the cutting is effected by a method which includes well-known elements which necessarily enter into the operation of a bobbin changing loom. Also, it will be seen that the shuttle is provided with a guide eye and a delivery eye so positioned as to cause the thread to extend across the tops of the rings on the head of the depleted bobbin. Furthermore, the brush assists in drawing the thread taut between the shuttle eye and the guide and operates merely by the forward sweep of the lay. The brush is located between the hook and the cloth so that no bend will be formed in that part of the thread which is to be cut, and the wing 46 contributes to tautness of the thread when lowered at the time of transfer.

Having thus described by invention it will be seen that changes and modifications may be made therein by those skilled in the art without departing from the spirit and scope of the invention and I do not wish to be limited to the details herein disclosed, but what I claim is:

1. In a weft replenishing loom having a lay and a shuttle thereon and having a transferrer arm to move downwardly on a weft replenishing beat of the loom to insert a fresh supply of weft into the shuttle, that improvement comprising a shuttle eye to effect delivery of the weft from the top of the shuttle, means carried by the shuttle presenting a surface over which the weft from r the delivery eye extends, and an element located coming and outgoing bobbins, means to locate the thread of the outgoing bobbin along the line of contact between the rings of the incoming and outgoing bobbins, and means to cause said mutual engagement of the metallic rings of the incoming and outgoing bobbins to cause said rings to sever the thread.

3. In a weft replenishing loom wherein weft replenishment is accompanied by mutual engagement between the metallic rings of the incoming and outgoing bobbins, a pair of spaced shuttle carried guides, one located on one side of the rings of the outgoing bobbin with reference to the length of the latter and the other located on the opposite side of the last named rings, to locate the thread of the outgoing bobbin between the rings of the incoming and outgoing bobbins, and means to cause mutual engagement of the rings of the-incoming and outgoing bobbins, to cause said rings to sever the thread during the replenishing operation.

4. In a weft replenishing loom having a shuttle carrying a bobbin provided with metallic rings and having a reserve bobbin also provided with metallic rings, means to lead the thread of the bobbin in the shuttle along a path lying between the rings of the two bobbins, and means to cause engagement between the rings of the two bobbins to cause cutting of the thread.

5.. In a weft replenishing loom having a shuttle carrying a bobbin provided with metallic rings and having a reserve bobbin also provided with metallic rings, means to guide the weft of the bobbin in the shuttle across the top of the rings of said bobbin in the shuttle, and means to force the reserve bobbin into the shuttle and cause engagement between the rings of both bobbins along the line traversed by the weft to sever the latter.

6. In a weft replenishing loom having a shuttle carrying a bobbin provided with metallic rings and having a reserve bobbin also provided with metallic rings, means to deliver the weft thread from the bobbin in the shuttle at the top of the shuttle, means to guide said weft thread across the rings of the bobbin in the shuttle, and means to force the reserve bobbin downwardly to replace the bobbin in the shuttle and sever the thread by engagement of the rings of the two bobbins.

'7. In a weft replenishing loom having a shuttle carrying a bobbin provided with metallic rings and having a reserve bobbin also provided with metallic rings, means carried by the shuttle to cause the weft to lie in an oblique line across the top of the rings of the bobbin in the shuttle, and means to force the reserve bobbin into the shuttle and against said thread to cause engagement of the rings of the two bobbins; to out said thread.

8. In a weft replenishing loom having a shuttle carrying a bobbin provided with metallic rings and having a reserve bobbin also provided with metallic rings, a shuttle eye at one end of the shuttle to deliver the thread from the bobbin in the shuttle at the top of the shuttle, a guide for the thread on that side of the rings of the bobbin in the shuttle opposite the shuttle eye, the shuttle eye and guide being located to direct the weft thread over the top of the rings of the bobbin in the shuttle, and means to force the reserve bobbin into the shuttle and cause engagement between the rings of both bobbins to cut the thread.

9. In a weft replenishing loom having a shuttle carrying a bobbin provided with metallic rings and having a reserve bobbin also provided with metallic rings, an eye on the shuttle to deliver the thread of the bobbin in the shuttle at the top of the latter, a thread guide at the top of the shuttle, the rings of the bobbin in the shuttle being located between the shuttle eye and the guide with respect to the length of the shuttle and under a thread extending from the shuttle eye to the guide, and means to force the reserve bobbin into. the shuttle to cause engagement of the rings of the two bobbins to cut the thread.

10. In a weft replenishing loom having a shuttle carrying a bobbin provided with metallic rings and having a reserve bobbin also provided with metallic rings, means to deliver the thread of the bobbin in the shuttle at the top of the latter, a guide for the thread located on that side of the rings of the bobbin in the shuttle opposite the shuttle eye, means to draw the thread taut between the shuttle eye and the guide, and. means to insert the reserve bobbin. into the shuttle and cause engagement between the rings of the two bobbins to cut the thread.

11.. In a weft replenishing loom having a backwardly and forwardly moving lay which carries a shuttle containing a bobbin provided with metallic rings, a reserve bobbin to be inserted into the shuttle. also having metallic rings, a shuttle eye to deliver the thread from the bobbin in the shuttle at the top of the latter, a thread guide on the top of the shuttle located on that side of the rings of the bobbin in the shuttle opposite the shuttle eye, stationary means operative due to forward motion of the lay to engage the thread at a point between the guide and the cloth being woven to draw the thread taut between the shuttle eye and the guide, and means to force the reserve bobbin into the shuttle to cause engagement between the rings of the two bobbins to cut the thread.

12. In a weft replenishing loom having a back.- wardly and forwardly moving lay which carries a shuttle containing a bobbin provided with metallic rings, a reserve bobbin to be inserted into the shuttle also having metallic rings, two spaced members carried by the top of the shuttle and between which the weft of the bobbin in the shuttle when. taut extends across the upper parts of the rings of the bobbin in the shuttle in the direction of the length of the last named bobbin, stationary flexible means to engage the weft and draw the same taut in a straight line between said members and across the upper parts of the rings of. the bobbin in the shuttle during forward motion of the lay, and means to insert the reserve bobbin into the shuttle to cause engagement between the rings of the reserve bobbin and the upper part of the rings of the bobbin in the shuttle to cut the thread.

13. In a weft replenishing loom having a backwardly and forwardly moving lay which carries a shuttle containing a bobbin provided with metallic rings, a reserve bobbin to be inserted into the shuttle also having metallic rings, a stationary brush, a pair of members both located on top of the shuttle and spaced from each other and both located on the same side of the brush, the rings of the bobbin in the shuttle being located between said members and the weft of the bobbin in. the shuttle being led over the top of the latter and guided by said members to lie over the rings of the bobbin in the shuttle, forward motion of the lay causing engagement between the weft and the brush to draw the thread taut between said members, and means to insert the reserve bobbin into the shuttle and cause engagement between the rings of the two bobbins to cut the taut thread.

14. In a weft replenishing loom having a shuttle with a bobbin provided with metallic rings and having a reserve bobbin also provided with metallic rings and wherein a rolling contact is established between the rings of the two bobbins during the simultaneous descent of the reserve bobbin into the shuttle and forward motion of the lay during a weft replenishing operation of the m, the combination of means to place the thread of the bobbin in the shuttle between said rings of the two bobbins to cause severing of said thread by said rings due to the rolling contact during the replenishing operation.

15. In a weft replenishing loom having a shuttle with a weft compartment containing a bobbin provided with metallic rings and the loom having a reserve bobbin also provided with metallic rings, weft tension means in the shuttle to exert frictional resistance to the passage or weft from the compartment to a point outside the shuttle, a delivery eye to deliver the weft after it leaves said weft tension means at the top of the shuttle, a weft guide on that side of the rings opposite the delivery eye, means to tension that part of the weft extending from the guide in a direction away from the rings to draw said thread taut between the delivery eye and said guide and over the rings, and transfer means to move the reserve bobbin into the shuttle and cause engagement between the rings of the two bobbins to cut the thread.

, RICHARD G. TURNER. 

